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Added format flags to lfsr_format

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This is mainly to solve the weird check-hole where passing CKPROGS/
CKREADS as mount flags has no effect on lfsr_format (I mean, it'd be a
bit silly if it did somehow):

  LFS_F_RDWR              0  // Format the filesystem as read and write
  LFS_F_CKPROGS  0x00000010  // Check progs by reading back progged data
  LFS_F_CKREADS  0x00000020  // Check reads via parity bits/checksums

This makes lfsr_format a more cumbersome interface, but I don't know if
this is necessarily a bad thing. There's always risk of data loss when
calling lfsr_format, so maybe it should be a pain to call.

At the very least, format flags may be useful in the future for
enabling/disabling format-time things such as the planned block-map,
parity-tree, etc. Though it's unclear if such significant settings
should be format flags or somehow encoded as fields in our config
struct.

---

The LFS_F_* format flags of course ended up conflicting with our
internal LFS_F_* flags, so I renamed most of the internal flags to match
the closest flag set they participate in:

- LFS_F_TYPE        -> LFS_O_TYPE
- LFS_F_UNFLUSH     -> LFS_O_UNFLUSH
- LFS_F_UNSYNC      -> LFS_O_UNSYNC
- LFS_F_ORPHAN      -> LFS_O_ORPHAN
- LFS_F_ZOMBIE      -> LFS_O_ZOMBIE

- LFS_F_ORPHANS     -> LFS_I_ORPHANS
- LFS_F_UNCOMPACTED -> LFS_I_UNCOMPACTED

- LFS_F_TSTATE      -> LFS_T_TSTATE
- LFS_F_BTYPE       -> LFS_T_BTYPE
- LFS_F_DIRTY       -> LFS_T_DIRTY
- LFS_F_MUTATED     -> LFS_T_MUTATED

This may make it a bit less clear which flags are a part of the public
API, vs intended only for internal use, but at the very least our asserts
in format/mount/open/etc should catch most of these mistakes.

---

Code cost ended up being pretty minimal. Actually negative. This is the
second time we're _adding_ a feature that somehow saves code, though the
reality for this one is we're really just pushing constants up into the
user's stack frame. Still, it's a good indication the cost of format
flags is small:

           code          stack
  before: 36452           2680
  after:  36448 (-0.0%)   2680 (+0.0%)
This commit is contained in:
Christopher Haster
2024-08-12 13:50:36 -05:00
parent dffd8fa0fa
commit acad3a3143
21 changed files with 785 additions and 678 deletions
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lfs.h
+29 -26
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@@ -119,7 +119,7 @@ enum lfs_type {
LFS_TYPE_REG = 1,
LFS_TYPE_DIR = 2,
// internally used types
// internally used types, don't use these
LFS_TYPE_BOOKMARK = 4,
LFS_TYPE_ORPHAN = 5,
LFS_TYPE_TRAVERSAL = 9,
@@ -139,18 +139,25 @@ enum lfs_type {
#define LFS_O_CKMETA 0x00001000 // Check metadata checksums
#define LFS_O_CKDATA 0x00002000 // Check metadata + data checksums
// internally used flags
#define LFS_F_TYPE 0xff000000 // The file's type
#define LFS_F_UNFLUSH 0x00100000 // File's data does not match disk
#define LFS_F_UNSYNC 0x00200000 // File's metadata does not match disk
#define LFS_F_ORPHAN 0x00400000 // File does not exist
#define LFS_F_ZOMBIE 0x00800000 // File has been removed
// internally used flags, don't use these
#define LFS_O_TYPE 0xff000000 // The file's type
#define LFS_O_UNFLUSH 0x00100000 // File's data does not match disk
#define LFS_O_UNSYNC 0x00200000 // File's metadata does not match disk
#define LFS_O_ORPHAN 0x00400000 // File does not exist
#define LFS_O_ZOMBIE 0x00800000 // File has been removed
// File seek flags
#define LFS_SEEK_SET 0 // Seek relative to an absolute position
#define LFS_SEEK_CUR 1 // Seek relative to the current file position
#define LFS_SEEK_END 2 // Seek relative to the end of the file
// Filesystem format flags
#define LFS_F_RDWR 0 // Format the filesystem as read and write
#define LFS_F_CKPROGS 0x00000010 // Check progs by reading back progged data
#ifdef LFS_CKREADS
#define LFS_F_CKREADS 0x00000020 // Check reads via parity bits/checksums
#endif
// Filesystem mount flags
#define LFS_M_RDWR 0 // Mount the filesystem as read and write
#define LFS_M_RDONLY 1 // Mount the filesystem as read only
@@ -161,21 +168,14 @@ enum lfs_type {
#define LFS_M_FLUSH 0x00000040 // Open all files with LFS_O_FLUSH
#define LFS_M_SYNC 0x00000080 // Open all files with LFS_O_SYNC
#define LFS_M_MTREEONLY \
0x00010000 // Only traverse the mtree
#define LFS_M_MTREEONLY 0x00010000 // Only traverse the mtree
#define LFS_M_MKCONSISTENT \
0x00000100 // Make the filesystem consistent
#define LFS_M_LOOKAHEAD \
0x00000200 // Populate lookahead buffer
#define LFS_M_LOOKAHEAD 0x00000200 // Populate lookahead buffer
#define LFS_M_COMPACT 0x00000800 // Compact metadata logs
#define LFS_M_CKMETA 0x00001000 // Check metadata checksums
#define LFS_M_CKDATA 0x00002000 // Check metadata + data checksums
// internally used flags
#define LFS_F_ORPHANS 0x01000000 // Filesystem may have untracked orphans
#define LFS_F_UNCOMPACTED \
0x08000000 // Filesystem may have uncompacted metadata
// Filesystem info flags
#define LFS_I_RDONLY 0x00000001 // Filesystem mounted read only
#define LFS_I_CKPROGS 0x00000010 // Filesystem mounted with LFS_M_CKPROGS
@@ -192,6 +192,10 @@ enum lfs_type {
#define LFS_I_UNCOMPACTED \
0x08000000 // Filesystem may have uncompacted metadata
// internally used flags, don't use these
#define LFS_I_ORPHANS 0x01000000 // Filesystem may have untracked orphans
// Block types
enum lfs_btype {
LFS_BTYPE_MDIR = 1,
@@ -200,21 +204,19 @@ enum lfs_btype {
};
// Traversal flags
#define LFS_T_MTREEONLY \
0x00010000 // Only traverse the mtree
#define LFS_T_MTREEONLY 0x00010000 // Only traverse the mtree
#define LFS_T_MKCONSISTENT \
0x00000100 // Make the filesystem consistent
#define LFS_T_LOOKAHEAD \
0x00000200 // Populate lookahead buffer
#define LFS_T_LOOKAHEAD 0x00000200 // Populate lookahead buffer
#define LFS_T_COMPACT 0x00000800 // Compact metadata logs
#define LFS_T_CKMETA 0x00001000 // Check metadata checksums
#define LFS_T_CKDATA 0x00002000 // Check metadata + data checksums
// internally used flags
#define LFS_F_TSTATE 0x0000000f // The current traversal state
#define LFS_F_BTYPE 0x000000f0 // The current traversal btype
#define LFS_F_DIRTY 0x00040000 // Filesystem modified during traversal
#define LFS_F_MUTATED 0x00080000 // Filesystem modified by traversal
// internally used flags, don't use these
#define LFS_T_TSTATE 0x0000000f // The current traversal state
#define LFS_T_BTYPE 0x000000f0 // The current traversal btype
#define LFS_T_DIRTY 0x00040000 // Filesystem modified during traversal
#define LFS_T_MUTATED 0x00080000 // Filesystem modified by traversal
// GC flags
#define LFS_GC_MTREEONLY \
@@ -810,7 +812,8 @@ typedef struct lfs {
//
// Returns a negative error code on failure.
//int lfs_format(lfs_t *lfs, const struct lfs_config *config);
int lfsr_format(lfs_t *lfs, const struct lfs_config *cfg);
int lfsr_format(lfs_t *lfs, uint32_t flags,
const struct lfs_config *cfg);
#endif
// Mounts a littlefs